In general, anal disorders, including anal fissure, anal ulcer, and acute hemorrhoidal disease are common, benign conditions of the anal canal, which affect subjects of all ages, races and sexes. However, these conditions can be problematical to treat and inconvenient if not painful to endure. A subject with an anal fissure or ulcer frequently experiences anal pain and bleeding, the pain being more pronounced during and after bowel movements.
Hemorrhoids are specialized vascular areas lying subjacent the anal mucosa. Symptomatic hemorrhoidal disease is manifest by bleeding, thrombosis and/or prolapse of the hemorrhoidal tissues. Commonly, internal hemorrhoidal tissue bulges into the anal canal during defecation causing bleeding and pain. As the tissue enlarges, further bleeding and pain, prolapse and thrombosis can ensue. The thrombosis of hemorrhoids is another cause of bleeding and pain.
The underlying causes of these anal disorders are poorly understood, but these conditions may be associated with infectious agents and infections of the surrounding tissue, wherein the tissue has become contaminated. The case of anal fissure/ulcer, an abnormality contributing to the disease appears to be an as-yet-unidentified problem of the internal anal sphincter muscle. The internal sphincter is a specialized, involuntary muscle arising from the inner circular muscular layer of the rectum. Intra-anal pressure measurements obtained from people suffering from typical anal fissure/ulcer disease show an exaggerated pressure response to a variety of stimuli. The abnormally high intra-anal pressure is generated by the internal sphincter muscle and is responsible for non-healing of the fissure or ulcer and the associated pain.
Various therapies have been devised to treat these anal disorders. Typical, non-surgical therapy includes bulk laxatives and sitz baths. Sitz baths are helpful because they induce relaxation of the anal sphincter mechanism. See e.g., Shafik, “Role of warm-water bath in anorectal conditions: The thermosphincteric reflex, “J. Clin. Gastroenterol., 16:304-308, 1993.
Topical anal therapy is also used in an effort to promote healing, relieve pain, and reduce swelling and inflammation. Many preparations have been tried including those containing local anesthetics, corticosteroids, astringents, and other agents. However, none of these preparations has been shown conclusively to reduce the healing time or to reliably ameliorate associated pain and some of the treatments, such as Neosporin ointment, are very sensitizing. In addition, antibiotics have not been found useful in treating the diseases. There is a need in the art to provide compositions useful to reduce healing times, alleviate pain and promote healing of the affected rectal and anal tissues.